1. Field of the Invention
The present invention relates to a color conversion processing method of converting image data having color information represented in form of a target device use into image data having color information represented in form of a printer use so that a printer reproduces colors to be created using a target device such as a printing machine, a color conversion processing apparatus for converting image data having color information represented in form of a target device use into image data having color information represented in form of a printer use, and a color conversion processing program storage medium storing a color conversion processing program which causes an information processing apparatus such as a computer to operate as such a color conversion processing apparatus.
2. Description of the Related Art
Hitherto, when a printing machine is used to perform a color image printing, it is performed prior to the color image printing that a color printer and the like is used to create a proof image which is extremely similar in color to an image to be printed in the printing machine. When the color printer and the like is used to create the proof image, the proof image is created in such a manner that detected are a color reproduction quality (a printing profile) describing an association between image data and a color of the actual printed matter, which is associated with a printing machine of interest, and a color reproduction quality (a printer profile) describing an association between image data and a color of the image to be actually printed out, which is associated with a printer of interest; the printing profile is combined with the printer profile to create a link profile; and image data for printing is converted into image data for a printer in accordance with the link profile, so that the proof image is created in accordance with the image data for a printer thus converted. In this manner, it is possible to create a proof image greatly close to the actual printed matter in color (cf. for example, Japanese Patent Application Laid Open Gazette Toku-Kai. 2002-139381).
In a case where the printer is a laser printer for forming an image using color toners of for example, C (cyan), M (magenta), Y (yellow), and K (black), there is a possibility that accumulation of a large amount of color toners of C, M, Y, and K upon the same pixel causes a pile of color toners to collapse, so that an image defect brings about. Thus, in some case, the extent of superposition of color toners (total amount of color toners needed for drawing a pixel) is restricted. Also in a case where the printer is an ink jet printer for forming an image using color inks of a number of colors (for example, six colors), there is a possibility that drawing of the same pixel by a large amount of inks causes over-concentration, so that an image defect brings about. Thus, in some case, the total amount of inks needed for drawing a pixel is restricted.
According to such a type of printer, a device signal constituting image data is not used directly to control an amount of toners and an amount of inks for the printer, and the device signal is processed so as to be restricted in order to prevent the occurrence of an image defect.
As a printer conversion processing section for performing such a conversion processing, there is known hardware and software for performing a restriction processing at the time of printing through combination of functions. However, in some method of the conversion processing, it takes a lot of time for the conversion processing and thus it takes a lot of time for printing.
Further, in the event that hardware and software are constructed to perform a restriction processing through combination of functions, it is difficult to alter the hardware and the software, even if a suitable processing method of the restriction is developed. And thus the processing method of the restriction is substantially fixed on a processing method incorporated into a driver of a printer from the first.